270 THE PLANT WORLD 



rooms which are to be found on the market, the most highly prized being 

 the morels and the truffles. 



Three remaining shelves indicate some phases of the scientific work. 

 In the large test tubes are new cultures of the spawn of many species 

 of mushrooms, and these are supplemented by photographs showing the 

 methods of making cultures. 



There are also shown preserved specimens and photographs of interest- 

 ing edible mushrooms, which may be found in pastures, in lawns, and on 

 decaying trees. 



Plant breeding. — A sixth case, containing an exhibit prepared by Dr. 

 H. J. Webber, shows some of the work that has been accomplished in the 

 improvement of plants by breeding. Various improved types of cotton 

 are exhibited by means of photographs and specimens illustrating the 

 processes used in producing hybrids and new fixed types, and in the selec- 

 tion and improvement of imported types, such as Egyptian cottons. 



Here is also illustrated the advance that has been made in the produc- 

 tion of hardy oranges by crossing the hardy Trifoliate orange with the 

 tender and edible sweet orange, and in the production of improved and 

 earlier varieties of the "kid glove," or Tangerine, orange, as well as 

 other new and improved types. 



FIBER-PLANT INVESTIGATIONS. 



The principal plant fibers used in the textile industries of this coun- 

 try — in twines, cordage, rope, thread, yarn, and woven goods — are shown 

 in the forms in which they are found in commerce as they pass from the 

 producer to the manufacturer. 



Living plants, with bales of fibers. — The exhibit is outlined by com- 

 mercial bales of hemp, flax, cotton, jute, manila, and sisal as these are 

 found on the market, and in most instances these bales are accompanied 

 by growing plants showing the source of the fiber. Since cotton, hemp, 

 and flax are the only fiber plants cultivated commercially in this country, 

 most of the others had to be imported — manila from the Philippines, sisal 

 from Yucatan, jute from India, and the various istle or Tampico fiber 

 plants from Mexico. 



Hard and soft fibers. — In the center of the fiber group are two glass 

 cases, one containing samples of hard fibres — manila, sisal, New Zealand, 

 Mauritius, and istle, used chiefly for binder twine, rope, and cordage, 

 and the other containing samples of typical cottons, such as American 

 Upland, Sea Island, Egyptian, and Indian, and the soft fibers or bast 

 fibers — hemp, flax, jute, and ramie — used more largely in woven goods 

 and for small twines. 



Ropes and twines. — Samples of manila and sisal rope and binder 

 twines, and also flax, hemp and jute twines, accompany the specimens 

 of raw fiber, but no attempt has been made to exhibit many forms of 

 articles or to show the different stages in the processes of manufacture. 



SEED LABORATORY. 



Seed-testing apparatus. — The apparatus used in making tests of seeds 

 for mechanical purity and for germination, including special cleaning 

 devices, forceps, and lenses for purity testing, and including also the 

 Improved Standard Germinating Chamber, is exhibited. 



Weed seeds. — Under magnifiers and in bulk are shown the weed seeds 



